1. Field of the Invention
The present invention relates to a capsule for administration to ruminants for the prevention or treatment of disorders particularly hypomagnesemia and grass tetany.
2. Description of the Prior Art
There is described in our Australian Patent Specification No. 470,538 and a capsule which is adapted to be administered per os to pass into the rumen to supplement the magnesium intake of the ruminant for the purpose of combating grass tetany, the disorder arising from magnesium deficiency.
Briefly, the capsule described in the above patent specification comprises a pair of semi-cylinders composed of magnesium or an alloy thereof. The interior of each of the semi-cylinders is covered by a coating of a resiliently flexible electrically insulating material which is so formed as to provide a hinge which links the two semi-cylinders. The two cylinders are thus pivotal from a closed condition in which they define a closed cylinder which can be administered per os, to an open position which they assume in the reticulo-rumen (rumen). The interior of each semi-cylinder houses a metal, for example, steel wool, which is lower in the electrochemical series than magnesium and which is electrically connected by means of screws or rivets to the magnesium or magnesium alloy which forms the body of the semi-cylinder. When the other metal is immersed in the contents of the rumen, the other metal acts as a cathode and the electrolytic effect thus created provides a high dissolution rate for the magnesium or alloy. Further details of this previously proposed capsule may be obtained from the above patent specifications.
Although this previously proposed capsule is effective in operation, it is relatively expensive to produce in that it requires a separate cathode plus means for attaching, and electrically connecting, the cathode to the body of the semi-cylinder. Commercially, capsules for the treatment of magnesium deficiencies in ruminants are highly cost-sensitive and a requirement exists for a capsule which can be produced more cheaply.